STUCCO INSPECTIONS, INC.
FAQ Answers - Stucco Inspections
- What are Exterior Insulation and Finish Systems (EIFS)?
- How does water enter behind the EIFS?
- Why does water intrusion occur behind EIFS and why is it important to discover it?
- Is the location of water entry visible and is the damage visible?
- Should I have my EIFS home periodically checked for elevated moisture levels?
- Can damaged homes be repaired and does the EIFS cladding have to be removed?
- What are the repair objectives?
- Should the repair be monitored?
- How should the home be maintained?
What are Exterior Insulation and Finish Systems (EIFS)?
The most common type of Exterior Insulation and Finish Systems, sometimes referred to as synthetic stucco, typically consists of five components: adhesive, insulation board, a base coat into which a fiberglass mesh is embedded, and a decorative finish coat in the desired color. This type of system is called a face sealed barrier EIFS and resists water penetration at its outer surface. It is not intended to drain water that gets behind it. It differs from other types of cladding that have a weather resistant barrier behind the cladding and/or may have air spaces between the cladding and substrate.There are many types of cladding materials that appear like stucco. Traditional stucco is made of cement and is different than exterior insulation finish systems cladding which use a foam plastic insulation board, a polymer/cement base coat, glass fiber mesh and a polymer modified finish coat. Other types of “hybrid” stucco include direct applied polymer/cement base coat to a substrate, or traditional stucco with an acrylic finish coat.
How does water enter behind the EIFS?
Interfaces between EIFS and dissimilar materials are a common source of water intrusion, not the EIFS lamina (base and finish coats). The most frequent source of water intrusion is windows. Water frequently enters the EIFS at window locations via two ways: 1) either the joint around the perimeter of the window; 2) through seams and joints in the window construction itself. Large quantities of water that can result in some of the most severe damage have frequently been discovered entering behind where a roof meets and terminates at the lower edge in a wall. Other potential sources of water intrusion are chimneys, decks and any other penetration of the EIFS lamina.
Why does water intrusion occur behind EIFS and why is it important to discover it?
Water intrusion occurs in a number of ways, through and/or around building components such as windows, doors, gable vents, penetrations, variety of flashing and construction details. Water intrusion also occurs when maintenance of these components and other critical areas like caulk joints, is ignored. It is important to discover the occurrence of water intrusion as water can enter behind the cladding and wet unprotected substrate (sheathing), and in some cases the wood structural members. Depending upon climate and the overall makeup of the wall assembly, the wall may not readily dry out. As water intrusion continues to occur undetected in a particular area, it can accrue to levels substantial enough to cause damage. Early detection of water intrusion is the key to minimizing or preventing such damage.
Is the location of water entry visible and is the damage visible?
No. The location of water entry is often difficult to see, and the damage to substrate and structural members behind the exterior wall cladding frequently cannot be detected by visual inspection.
Should I have my EIFS home periodically checked for elevated moisture levels?
Yes. Testing should be done on the initial inspection and then re-inspected every 3 years unless selling the house which requires an inspection to be conducted within 120 days to be considered current by industry standards; moisture readings are current for 30 days. A combination of two moisture meters, non-invasive meter that scans through the wall for the presence of moisture without penetrating the EIFS lamina, and a probe-type meter that penetrates the EIFS lamina and gives moisture readings of materials in contact with the probes should be used. Only a professional experienced in EIFS water intrusion inspections should perform this test. Testing is recommended to be conducted in accordance with the latest edition of Moisture Testing Guide for Wood Frame Construction Clad with Exterior Insulation and Finish Systems that is published by the New Hanover County Inspections Department in Wilmington, NC.
Can damaged homes be repaired and does the EIFS cladding have to be removed?
Any repair method undertaken should render the house in a serviceable condition. Performance criterion used to determine if a serviceable condition is being sustained is a moisture assessment. Such a condition exists when damage or excessive moisture is not detected behind the EIFS cladding. This may be true even if the EIFS manufacturer’s standard specifications and construction details were not originally followed. Localized removal of EIFS may be necessary to facilitate repairs where damage is discovered. Total removal of the cladding may not be necessary.
What are the repair objectives?
The primary objective of repair methods is to eliminate water intrusion. Repairs should e made where elevated moisture or structural integrity of the material is impaired. Where structural damage has occurred, those areas require replacement of decayed lumber in addition to eliminating the source of water intrusion. Areas of elevated moisture in the absence of damage or decay may require no more than eliminating the source of water intrusion. It has been discovered that undamaged but wet substrate can dry out over time once the source of the water intrusion has been eliminated. Repair methods should address leaks associated with but not limited to:
- Roofs – install effective kick-out flashing at roof to wall intersections, diverter flashing around trapped-valleys, rake flashing.
- Caulk joints – install effective caulk joints.
- Windows and doors – caulk window jam to sill joint and joints in any molding surrounding the window or door. Specially designed sill flashing is needed below most types of windows and most windows that are mulled together.
- Decks – install effective flashing.
- Chimneys – install effective cap flashing, cricket flashing at trapped valley, effective kick-out flashing for roof-rake wall intersections.
- Other penetrations – install effective caulk joint and or flashing.
- Cracks and damaged EIFS lamina – repair according to manufacturer’s specifications.
Effective implies that flashing and caulking prevents water intrusion. Special care, craftsmen skill, and design consideration are required to make repairs and install flashing.
Repairs for every component, penetration, architectural detail and flashing detail have not been submitted or reviewed by the EIFS Review Committee. Some repair methods were developed in laboratory conditions and are currently being tested and monitored in the field for effectiveness. Preliminary test data indicates that effective repairs to some limited components frequently used in EIFS can be achieved. The repairs do not restore the windows, flashing or EIFS to match the EIFS manufacturer’s original specifications or details, but focuses on eliminating leaks by modifying the as-built conditions. The effectiveness of any repair is dependent upon accurate diagnosis of the source of water intrusion and the skill of the contractor making the repair. The repair is performing successfully when elevated moisture diminishes to an acceptable level over time and does not recur in sustained elevated levels in the long term.
Should the repair be monitored?
Yes. A professional experienced in EIFS water intrusion inspections should be hired to perform follow up inspections within six months following the repair. Then, once every year the effectiveness of the repair should be monitored as part of the whole house moisture survey. If the repair is not successful, elevated moisture levels will be detected and the repair method should be elevated for effectiveness and reason for failure. After making additional repairs, follow up with another inspection until such time the moisture level becomes acceptable.
How should the home be maintained?
Frequent visual inspection should include thorough checking of windows, flashing and sealant/caulk. Damaged flashing should be repaired or replaced immediately. Cracks or deteriorated sealants should be repaired or removed and replaced. Periodic moisture testing would be prudent, especially for houses that were diagnosed with elevated moisture levels. Homeowners should refer to the manufacture’s maintenance and repair instructions. Information is also available from the NAHB Research Center’s House Base Hotline at 800 898-2842.